1. Field of the Invention
The present invention relates to distribution and/or receipt of video program signals and, more particularly, to distribution and/or receipt of satellite television signals, over a network utilizing multicasting IP and Ethernet protocols.
2. Related Art
With the proliferation of the Internet and broadband networks, sending digital video, audio and/or data over an IP (Internet Protocol) network is becoming very advantageous. IP networks provide a structured protocol transport structure that may be exploited to provide one or more different data streams over a network each data stream of which may be acquired by one or more receivers connected to the network. This is known as multicasting. Multicasting IP datagrams are transmitted to a host group, a set of zero or more hosts identified by a single IP destination address. The IP datagram is then delivered to all members of its destination host group (corresponding to an IP multicast address).
By utilizing multicast networking, one digital data server can direct content to multiple clients simultaneously. This optimizes bandwidth use, which would otherwise require unicasting packets to several clients (i.e. providing a bit stream of packets or data to each individual address).
If the source of the digital data is a satellite system, a user, through the user's satellite receiver, set top box or the like, must select a specific satellite, transponder and PIDs (or SCIDs) to request the proper data packets in order to acquire a particular channel or program. The program is transmitted from the satellite in the form of packetized program streams, wherein the specific program streams associated with a particular program having identification information, such as program ID (PID) included therein. Using the identification information, the satellite receiver filters out the packetized data stream to acquire the desired program stream. The satellite receiver must thus be able to make the proper selection of program bit stream or signal for the requested satellite channel or program. The satellite receiver may be connected to various client set top boxes, which may be coupled to display devices, through a data network, such as an Ethernet based network.
An approach in order to have the satellite receiver select the appropriate satellite channel is to have the digital server generate a mapping table of parameters of each satellite transmitted channel to each assigned IP address. When the receiver or set top box is commanded to tune to a particular elementary stream (channel or the like), the set top box would do a table look-up to determine the address to which to request data.
A disadvantage to this method is in the processing time wasted in generating this table, downloading this table to the client set top box(es), and in the set top box performing the table look-up during tuning. Additionally, this table may need to be regenerated and re-downloaded when new elementary stream information becomes available or existing elementary stream data is no longer available. Moreover, this table would consume valuable memory on both the digital data server and the client set top box.
It is thus evident from the above discussion that what is needed is an efficient manner of distributing satellite program signals from a data server to multiple clients.
It is thus further evident from the above discussion that what is needed is an efficient satellite television distribution system that efficiently provides multiple satellite television signals to any one or more satellite or set top box receivers.
This need and others are accomplished through application of the principles of the subject invention and/or as embodied in one or more various forms and/or structures such as are shown and/or described herein.